Intel Core Duo USB Issue: A Mischaracterized Bug

The Notebooks

In order to test this issue thoroughly, we looked at five notebooks:

ASUS W5A (Sonoma/Pentium M)

ASUS W5F (Napa/Core Duo)

Dell Inspiron E1705 (Napa/Core Duo)

Lenovo Thinkpad T60 (Napa/Core Duo)

Lenovo Thinkpad T43 (Sonoma/Pentium M)

The USB Devices

We tested with three USB devices:

Kingston Data Traveler Elite (USB 2.0)

Vantec NexStar 2 External 3.5" Hard Drive Enclosure (USB 2.0)

Not that this device is entirely externally powered

Microsoft Intellimouse Optical Blue (USB 1.0)

The Test

We standardized on Mobile Mark's Reader 2002SE test simply because that test is hardly CPU intensive, giving it a lot of time to spend in lower power states and potentially giving the asynchronous scheduler bug a good chance to impact battery life. 

	ASUS W5F	ASUS W5A	Dell Inspiron E1705	Lenovo Thinkpad T60	Lenovo Thinkpad T43
CPU:	Intel Core Duo T2400 (1.86GHz)	Intel Pentium M 750 (1.86GHz)	Intel Core Duo T2600 (2.16GHz)	Intel Core Duo T2600 (2.16GHz)	Intel Pentium M 780 (2.26GHz)
Chipset:	Intel 945G	Intel 915G	Intel 945G	Intel 945G	Intel 915G
Chipset Drivers:	Intel 7.2.2.1006	Intel 7.2.2.1006	Intel 7.2.2.1006	Intel 7.2.2.1006	Intel 7.2.2.1006
Memory:	1 x 512MB (DDR2-533)	1 x 512MB (DDR2-400)	2 x 512MB (DDR2-667)	2 x 512MB (DDR2-533)	2 x 512MB (DDR2-533)
Graphics:	Intel Integrated 945G Graphics	Intel Integrated 915G Graphics	Intel Integrated 945G Graphics	Intel Integrated 945G Graphics	Intel Integrated 915G Graphics
Video Drivers:	Intel 14.18.2	Intel 14.18.2	Intel 14.18.2	Intel 14.18.2	Intel 14.18.2
Desktop Resolution:	1280 x 768	1280 x 768	1920 x 1200	1400 x 1050	1024 x 768
Battery Capacity:	50 WHr	50 WHr	80 WHr	56 WHr	51 WHr